Canonical · Logic & Mathematics · Model

Bayes' Theorem

Thomas Bayes (published by Richard Price) · 1763

"Belief should update in proportion to evidence — Bayes' theorem is the exact math for how much a new piece of evidence should move your confidence."

The idea

Bayes never published this in his lifetime — a friend found it in his papers and printed it in 1763. It's the exact formula for how much a new piece of evidence should change what you believe.

Why it works

The takeaway — recall it first

Deterministic Chaos

"Fully deterministic systems — with no randomness anywhere in their equations — can still become practically unpredictable, because tiny differences in starting conditions grow exponentially over time until prediction becomes impossible."

Edward Lorenz · PaperContinue→